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Service bulletins for the 2020 Ram 4500

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

569 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

Bulletins, newest first
14003232023-05-30. Service bulletin. ELECTRICAL SYSTEM. Diesel Exhaust Fluid (DEF) Fluid Freezing Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find the following Diagnostic Trouble Code (DTC) has been set: ? P203E-00 - Reductant Level Sensor 1 Circuit Intermittent-Erratic. This bulletin involves replacing the urea delivery module and grade vent valve and updating the Dosing Control Unit (DCU) software.
18048232023-05-30. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING. wiTECH Small Leak Verification Test (SLVT) - P0456-EVAP SYSTEM SMALL LEAK
S22080000802023-05-30. Service bulletin. ELECTRICAL SYSTEM. Ambient Air Temperature Missing, Malfunction Indicator Lamp (MIL) Lamp On, Diagnostic Trouble Code (DTC) P0070-15 Ambient Air Temperature Sensor Circuit-Circuit Short to Battery or Open, P0073 Ambient Air Temperature Sensor Circuit High
S22230000632023-05-30. Service bulletin. ELECTRICAL SYSTEM. Ambient Temperature Sensor Servicing.
08045232023-04-17. Service bulletin. EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. Radio Over The Air Updating to 34.42 Software Version ? Mobile Wi-Fi inoperative upon start up. ? Hotspot gives 9No Internet9 connection message on phone when trying to connect to a device. This bulletin provides information regarding the latest Firmware Over The Air (FOTA) update and provides the service technician an overview of the steps a customer will need to take to complete the update. The radio software will be updated from 34.4 to 34.42.
S18080001522023-04-17. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). CEL (Check Engine Lamp) Illuminates, Recent PCM Replace or Flash Update Performed, Diagnostic Trouble Codes (DTCs) P057B Brake Pedal Position Sensor Circuit Performance, P1572 Brake Pedal Stuck, C0042-54 Brake Pedal Missing Calibration
S228A0000282023-04-17. Service bulletin. ELECTRICAL SYSTEM. Radio Remained On After Ignition Is Switched Off, Dead Battery From Excessive Radio Current Draw
S14080003842023-04-17. Service bulletin. ELECTRICAL SYSTEM. Start Stop Charging Warning Lamp Illuminated On, Intelligent Battery Sensor (IBS) State of Charge (SOC) Inaccurate, Battery Charging Message, Presence of IBS related Diagnostic Trouble Codes (DTCs), or Battery Warning Lamp On
08-038-232023-02-13. Service bulletin. BACK OVER PREVENTION:SOFTWARE. Radio Over The Air JR34.3 Updating to JR34.32.Software Version Customers may experience one or more of the following: Not be able to use Mobile Wi-Fi upon start up. Hotspot gives a no Internet connection message on phone when trying to connect to a device. This bulletin provides information regarding the latest Firmware Over The Air (FOTA) update and provides the service technician an overview of the steps a customer will need to take to complete the update. The radio software will be updated from JR34.3 to JR34.32. NOTE: National launch for this FOTA update is expected to begin February 20, 2023.
08-022-232023-02-13. Service bulletin. BACK OVER PREVENTION:SOFTWARE. Radio Over The Air Updating to 40.12 Software Version Mobile Wi-Fi inoperative upon start up. Hotspot gives 9No Internet9 connection message on phone when trying to connect to a device. This bulletin provides information regarding the latest Firmware Over The Air (FOTA) update and provides the service technician an overview of the steps a customer will need to take to complete the update. The radio software will be updated from 39.5 to 40.12.
S23180000012023-02-13. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. Diagnostic Trouble Code (DTC) P1400 ? Aftermarket Calibration Detected/Warranty Coverage Confirmation Required, Setting Falsely.
S1623000028 Rev.2023-02-13. Service bulletin. VEHICLE SPEED CONTROL; BACK OVER PREVENTION; POWER TRAIN; VISIBILITY; PARKING BRAKE. Outside Power Fold Rearview Mirror Noise Or Loose At Pivot. Mirror Contacts Door Window Glass In The Folded Position.
S1625000003 Rev.2023-02-13. Service bulletin. BACK OVER PREVENTION; EXTERIOR LIGHTING. Malfunction Indicator Lamp (MIL) Illumination. NOx Sensor Diagnostic Trouble Codes (DTCs) Diagnosis Information.
S23230000022023-02-13. Service bulletin. EQUIPMENT:ELECTRICAL. Washer Light On And Will Not Turn Off After Adding Washer Solvent.
08214222023-01-23. Service bulletin. EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.; EQUIPMENT; ELECTRICAL SYSTEM. Radio Over The Air Updates to JR34.3/JR34.4 and JR34.41
08095222023-01-17. Service bulletin. ELECTRICAL SYSTEM. UAX And UCX KR20.12 To PR40.1 Software Version Updates
21021222023-01-17. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Customers may comment on one or more of the following: When decelerating from a 1 to 2 gear shift, the vehicle may have a harshshift. From a 1 to 2 gear change there may be a perceived bump feeling, whilehaving a light pedal(Sales Codes ETL and ETN Only). A harsh shift from a 2 to 3 gear shift while at almost or wide openthrottle. A harsh shift from a 3 to 4 shift and heavy on the pedal, lifting offthe pedal, then back on the pedal again. While coasting down a grade, an abrupt deceleration may be felt. A clunk heard when shifting from park to reverse or drive. Cold engine flare during a shift. A delay when coasting down, vehicle is in a downshift at low speedsand then trying to accelerate. (The vehicle will have a hesitation as the vehicle tries to change gears to accommodate the new pedaldemand). Excessive shifting(DD and DP Only). Engine flare caused by the transmission releasing the clutch too early duringa 1 to 2 shift. Poor shift quality. Shift or gear hunting.
08119212023-01-17. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.; EQUIPMENT. UAX, UCX, UAV and UCV Radio Over the Air Software Version Updates This bulletin provides information regarding the latest Flash Over The Air (FOTA) update and provides the service technician an overview of the steps a customer will need to take to complete the update. The radio software will be updated to:DT with UAX and UCX - 34.31. All other vehicles and radio combinations - 34.2. The national launch for the FOTA will begin July 21, 2021. Customers may experience one or more of the following: SOS, Automatic SOS (ASOS) , assist calls not showing correct location(DT Vehicles with UAX and UCX Only). GPS inaccuracies(DT Vehicles with UAX or UCX Only). Uconnect radio apps are inoperable(DT Vehicles with UAX or UCX Only). SXM® button are greyed out(DT Vehicles with UAX or UCX Only). Intermittently, SXM loading screen is stuck(DT Vehicles with UAX or UCX Only). Uconnect App inoperative(DT Vehicles Only). Voice Recognition (VR) inoperative(DT Vehicles Only). Radio resets(DT Vehicles Only). Radio locks up, freezes or resets. Bluetooth device is slow to pair, or does not pair. GPS unable to load and find locations. Loss of saved radio presets. Display screen is back with no backlighting. No audio output coming from the radio. Cannot control audio volume. Rear view camera display will not turn off.
S20180000072023-01-17. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:GASOLINE:TURBO/SUPERCHARGER. Diagnostic Trouble Code (DTC) P0299 ? Turbocharger Underboost Additional Diagnostics
S21090000062023-01-17. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:OIL/LUBRICATION:SEALS/GASKETS. Oil Leak From The Oil Pan Gasket.
S21180000122023-01-17. Service bulletin. EXTERIOR LIGHTING. Malfunction Indicator Lamp (MIL) Illumination. Diagnostic Trouble Code (DTC) P0607 ? ECU Internal Performance, Set.
S21080000912023-01-17. Service bulletin. ELECTRICAL SYSTEM. When The PTO Is Engaged, The Engine RPM Will Surge And Cannot Increase above 1100 RPM. Diagnostic Trouble Codes (DTCs) P061B ? Internal Control Module Torque Performance, And/Or P064B ? PTO Control Module, Set.
S21230000552023-01-17. Service bulletin. ENGINE; SERVICE BRAKES. HD Truck Brake Pedal Feel On Gas Engine Equipped
S20250000072023-01-17. Service bulletin. EXTERIOR LIGHTING. Malfunction Indicator Lamp (MIL) Illumination. Diagnostic Trouble Code (DTC) P218F ? Reductant No Flow Detected set.
S21080001702023-01-17. Service bulletin. PARKING BRAKE. Head unit button stuck DTC code B14DA-2A

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.